From ccda7bc725f5ad883fef28781637737420c3a623 Mon Sep 17 00:00:00 2001
From: Winson Chung <winsonc@google.com>
Date: Thu, 3 Jun 2021 13:19:50 -0700
Subject: [PATCH] Workaround for apps to stop before removing the task

- With live tile enabled, the race between destroying the task and
  killing the process is more evident since the app may not get
  stopped at all.  For now, when dismissing, defer removing the
  task until we've finished the recents animation to allow the
  app to be stopped accordingly

Bug: 184899234
Test: Dismiss the task from overview, check that the app gets
      lifecycle events
Change-Id: Ib3ea479643d65859fe4cd580b4c347b87130a69d
---
 .../android/quickstep/RecentsActivity.java    |  3 +-
 .../android/quickstep/views/RecentsView.java  | 30 +++++++++++++------
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/quickstep/src/com/android/quickstep/RecentsActivity.java b/quickstep/src/com/android/quickstep/RecentsActivity.java
index 0e9e3ad029..d43bb24a1e 100644
--- a/quickstep/src/com/android/quickstep/RecentsActivity.java
+++ b/quickstep/src/com/android/quickstep/RecentsActivity.java
@@ -350,8 +350,7 @@ public final class RecentsActivity extends StatefulActivity<RecentsState> {
     public void startHome() {
         if (LIVE_TILE.get()) {
             RecentsView recentsView = getOverviewPanel();
-            recentsView.switchToScreenshot(() -> recentsView.finishRecentsAnimation(true,
-                    this::startHomeInternal));
+            recentsView.switchToScreenshotAndFinishAnimationToRecents(this::startHomeInternal);
         } else {
             startHomeInternal();
         }
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index 17d1afc168..166fd80970 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -176,6 +176,10 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         TaskThumbnailCache.HighResLoadingState.HighResLoadingStateChangedCallback,
         TaskVisualsChangeListener, SplitScreenBounds.OnChangeListener {
 
+    // TODO(b/184899234): We use this timeout to wait a fixed period after switching to the
+    // screenshot when dismissing the current live task to ensure the app can try and get stopped.
+    private static final int REMOVE_TASK_WAIT_FOR_APP_STOP_MS = 100;
+
     public static final FloatProperty<RecentsView> CONTENT_ALPHA =
             new FloatProperty<RecentsView>("contentAlpha") {
                 @Override
@@ -2423,8 +2427,11 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
                 if (success) {
                     if (shouldRemoveTask) {
                         if (dismissedTaskView.getTask() != null) {
-                            UI_HELPER_EXECUTOR.execute(() -> ActivityManagerWrapper.getInstance()
-                                    .removeTask(dismissedTaskId));
+                            switchToScreenshotAndFinishAnimationToRecents(() -> {
+                                UI_HELPER_EXECUTOR.getHandler().postDelayed(() ->
+                                        ActivityManagerWrapper.getInstance().removeTask(
+                                                dismissedTaskId), REMOVE_TASK_WAIT_FOR_APP_STOP_MS);
+                            });
                             mActivity.getStatsLogManager().logger()
                                     .withItemInfo(dismissedTaskView.getItemInfo())
                                     .log(LAUNCHER_TASK_DISMISS_SWIPE_UP);
@@ -2529,10 +2536,13 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         mPendingAnimation.addEndListener(isSuccess -> {
             if (isSuccess) {
                 // Remove all the task views now
-                UI_HELPER_EXECUTOR.execute(
-                        ActivityManagerWrapper.getInstance()::removeAllRecentTasks);
-                removeTasksViewsAndClearAllButton();
-                startHome();
+                switchToScreenshotAndFinishAnimationToRecents(() -> {
+                    UI_HELPER_EXECUTOR.getHandler().postDelayed(
+                            ActivityManagerWrapper.getInstance()::removeAllRecentTasks,
+                            REMOVE_TASK_WAIT_FOR_APP_STOP_MS);
+                    removeTasksViewsAndClearAllButton();
+                    startHome();
+                });
             }
             mPendingAnimation = null;
         });
@@ -2687,9 +2697,7 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
     protected void onConfigurationChanged(Configuration newConfig) {
         super.onConfigurationChanged(newConfig);
         if (LIVE_TILE.get() && mEnableDrawingLiveTile && newConfig.orientation != mOrientation) {
-            switchToScreenshot(
-                    () -> finishRecentsAnimation(true /* toRecents */,
-                            this::updateRecentsRotation));
+            switchToScreenshotAndFinishAnimationToRecents(this::updateRecentsRotation);
             mEnableDrawingLiveTile = false;
         } else {
             updateRecentsRotation();
@@ -3687,6 +3695,10 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         }
     }
 
+    public void switchToScreenshotAndFinishAnimationToRecents(Runnable onFinishRunnable) {
+        switchToScreenshot(() -> finishRecentsAnimation(true /* toRecents */, onFinishRunnable));
+    }
+
     /**
      * Switch the current running task view to static snapshot mode,
      * capturing the snapshot at the same time.